Techniques for fabricating and patterning transistors include photochemical patterning, for example, to construct source/drain electrodes and appropriate interconnections for functional organic circuits. Such methods, however, may have the processing disadvantage of relying on vacuum evaporated conductors for source, drain and thin dielectric layers. Although it is possible to produce low voltage (.about.5 V) transistors with thin gate dielectrics of SiO.sub.2 (.about.100 nm) by combining printing and low cost near-field photolithographic methods, solution processed dielectrics typically include thick (.about.1 .mu.m) spin cast or screen printed polymer films. Accordingly, the low capacitance of these layers restricts operation to voltages (.about.100 V) that may exceed voltages required for many applications.
High capacitance gate dielectrics of barium zirconate titanate formed by radio frequency magnetron sputtering have been successfully used for organic p-channel transistors, however, opportunities remain for convenient procedures for fabricating thin, low defect (pinhole-free) gate dielectrics of more conventional and easily processible materials. A need exists for fabricating transistors that incorporate an organic semiconductor and that can operate at low voltages, including anodization for thin (.about.50 nm), high capacitance gate dielectrics, and microcontact printing on electroless silver for high resolution (.about.1 .mu.m) source/drain electrodes.